This invention generally relates to seat assembly machines. More particularly, this invention relates to a machine for assembling vehicle seats having an independently moveable headrest alignment feature.
Typical modern day vehicles include driver and passenger seats having headrests that provide support for an individual's head. Headrests are particularly useful for preventing neck strain or injury as a result of a collision, for example.
Typical seat arrangements include a seat frame that provides support for an individual. The seat frame typically is covered by a cushion and a fabric covering. The headrest typically has two support posts that are received within corresponding portions of the seat frame. The covering over the seat typically has premade holes through which the headrest posts are inserted.
One challenge in making vehicle seats is properly aligning the openings in the seat frame and the openings in the seat cover material and maintaining that alignment during assembly so that the assembled arrangement has the openings properly aligned as needed for eventually inserting the headrest support posts. Various machines have been utilized to assemble seats that incorporate design features for aligning the frame openings and the cover openings. One drawback associated with most machines is that they do not consistently provide accurate alignment. This results in sometimes poorly aligned covers over the seat back which renders a particular unit unuseable in a vehicle. Under some circumstances the seat back can be removed from the fabric cover but this is a time-consuming and, therefore, expensive process. Under other conditions, it is not worth attempting to remove the seat back from the cover so that the unit is discarded. In either situation, there is waste and a loss of economies in production.
Typical assembly machines that include a headrest alignment feature have the headrest alignment structure fixed relative to a seat clamping structure so that the two only move together before or during an assembly process. While such arrangements provide for enhanced accuracy, there are difficulties associated with them. It is not always easy for an operator to ensure proper alignment during the seat assembly process. Additionally, such machines are only capable of handling a specific type of seat frame. If a different seat frame were used, the machine would need to be adjusted, which typically would require at least temporarily removing the machine from production and incurring labor costs for making adjustments to the machine setup to accommodate another seat design. Moreover, some seat frames have a headrest incorporated into the seat so that a separate headrest with posts is not necessary. Such seat frames cannot be accommodated in the machines that have a fixed headrest alignment feature.
There is a need for an improved seat assembly machine that is versatile and enhances accuracy. This invention addresses those needs while avoiding the shortcomings and drawbacks of the prior art.